Boiler Orifice Union

The Boiler Orifice Union is a specially milled union for 1/2" and 3/4" NPT pipes. ChemWorld also provides 1" NPT unions orifice assemblies. They orifice unions are designed to work with boiler orifice plates. The purpose of a boiler orifice plate is to reduce the flow rate and to eliminate steam flashing over the controller conductivity probe. Without this steam flow restriction, false reading may be sent to your boiler blowdown controller, resulting in the steam boiler blowdown valve to power on/off repeatedly. Boiler globe valves may also be used in place of orifice plates.

ChemWorld also provides timed sample kits and continuous sample kits for sampling steam boiler water.

Improper control of your boiler blowdown controller will also increase blowdown rates, increased energy costs, and increase steam boiler chemicals use.

• Part Number 1167244 for 1/2" diameter pipes.
• Part Number 1167245 for 3/4" diameter pipes.

For new steam boiler startups, consider purchasing our Steam Boiler Startup Kit.

Approximately how many lbs per hour can you blowdown through a 1/16" orifice in a 3/4" line? The boiler psi is about 100.

The flow rate would be approximately 1200 lbs/hr.

What is the maximum pressure for your Orifice Union?

The Max Pressure is 600 psi (41.4 bar)

What is the maximum temperature for your CWOU?

The Max Temperature is 486°F (252°C)

We bought a 3/4" Boiler Orifice Unioon with a 3/8" Orifice Plat. What would be the flow rate in gpm at 100psi for water?

Here is the chart for the flow information on Orifice Unions: